As cellular networks become more congested, network operators continue to deploy smaller cells on several orders of magnitude to meet projected demands. The presence of these smaller cells helps offload traffic from the macro cells, but may cause unwanted interference. In some situations, smaller cells may not be actively serving a user, but may continue to transmit at least the downlink common channels. This continued transmission may cause undesirable interference, especially where the density of access nodes is high. Additionally, these continued transmissions may expend energy unnecessarily. Therefore it may be beneficial to have access nodes enter a dormant state when they are not serving a user to limit interference and conserve power.
While placing the access nodes in a dormant state may prevent interference and save power, it creates new challenges for discovery and reactivation of the dormant access nodes.